From 1^st to 30^th October 2021, I visited the Department of Molecular Systems Biology in Helmholtz Center for Environmental Research – UFZ, Germany. During my stay, I tried to optimize the sample preparation for metaproteomics of gut microbiomes in zebrafish. Furthermore, I had the chance to be familiar with QIIME and a webserver to process, analyse and visualize microbiome data. I would like to thank the PROFISH project (090032/0869 Profish/401/104040), which financially supported my stay.